HP-UX Logical Volume Manager and MirrorDisk/UX Release Notes HP-UX 11i v3 (September 2011)

Table 1 LVM Fixes in HP-UX 11i v3 September 2011 Release (continued)
DescriptionDefect ID
There is a small performance penalty when VxFS 5.0.1 is used on a LVM logical volume since
LVM unnecessarily restricts async I/Os to 256KB.
QXCR1001101905
The lvextend command allocates one extent in the physical volume group which has one
physical volume and the remaining extents in the next physical volume group when the logical
volume has distributed pvg-strict policy.
QXCR1001110394
1
In a LVM shared volume group, if both internal resync (triggered by a physical volume
coming back online) and I/Os are targeted for the same extents (in any of the nodes), it may
lead to IOs hang when there is heavy I/O load and frequent intermittent disk failures.
QXCR1001110492
1
When run on a version 1.0 volume group, vgmodify -a coredumps or complains:QXCR1001112083
Physical Volume PV_name entry in new VGDA incorrect.
While creating a distributed PVG-Strict logical volume on a 1.0 volume group, LVM allocates
one extent in the physical volume group which has only one physical volume and the remaining
QXCR1001119089
extents in the next physical volume group that has more than one disk. Ideally, no extents
should have been allocated in the first PVG group in this case.
1 This defect was fixed in the April 2011 web release and listed in the April 2011 Release Notes.
Known issues and limitations
This section provides a list of known issues and limitations as known to HP at time of publication.
If workarounds are available, they are included.
Known issues
lvchange -M y on mirrored LV with snapshot hangs and causes I/Os on LV to hang
Defect ID: QXCR1001131631
Problem: While running lvchange to set the mirror write cache flag ON on a
mirrored logical volume with snapshot(s) when the logical volume is
open and I/Os to this logical volume are in progress, the lvchange
command could hang, causing I/O on the original logical volume
to hang.
Severity: Critical
Corrective Action: As mentioned in the manpage for lvchange -M, ensure that the
logical volume with snapshot(s) is not opened while attempting to set
the mirror write cache flag.
slvm IO hang in pv_cache_wait q of the PV which was offline
Defect ID: QXCR1001134963
Problem: I/Os to mirrored logical volume of a shared volume group hangs in
kernel when a physical volume comes back online and the logical
volume is MWC enabled.
Severity: Critical
Corrective Action: To come out of the hang situation, the server has to be rebooted.
LVM panic, slvmp: process bad reply, unknown reply
Defect ID: QXCR1001131097
Problem: Deactivating a shared volume group in the client when the server is
crashed would result in client panic with the following stack trace:
6 Logical Volume Manager and MirrorDisk/UX Release Notes